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  • Rectangle triangle problem

    1 September, 1997
    September 1997
    Triangle in rectangle

    If we label the distances AP, PB, CQ and QB as shown above then we can write three equations for the areas of the triangles as follows:

    Equations
    Ratio

    Notice that the two ratios are the same! If we call this ratio r then we can calculate a polynomial for r as follows:

    Polynomial

    Taking the positive root gives us the golden ratio:

    Phi
    • Log in or register to post comments

    Daz

    29 November 2019

    Permalink
    Comment

    For explaining a solution like this one that uses very few variables, it's much easier to read if the variables are named with different letters, but no subscripts.

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